writing - letters or symbols written or imprinted on a surface to represent the sounds or words of a language; "he turned the paper over so the writing wouldn't show"; "the doctor's writing was illegible"

mathematical notation - a notation used by mathematicians

musical notation - a notation used by musicians

choreography - a notation used by choreographers

chemical notation - a notation used by chemists to express technical facts in chemistry

poste restante - a notation written on mail that is to be held at the post office until called for (not in the United States or Canada)

commentary, comment - a written explanation or criticism or illustration that is added to a book or other textual material; "he wrote an extended comment on the proposal"

quotation, reference, acknowledgment, mention, citation, credit - a short note recognizing a source of information or of a quoted passage; "the student's essay failed to list several important citations"; "the acknowledgments are usually printed at the front of a book"; "the article includes mention of similar clinical cases"

footnote, footer - a printed note placed below the text on a printed page

N.B., nota bene, NB - a Latin phrase (or its abbreviation) used to indicate that special attention should be paid to something; "the margins of his book were generously supplied with pencilled NBs"

postscript, PS - a note appended to a letter after the signature

committal to writing, writing - the activity of putting something in written form; "she did the thinking while he did the writing"